export function getBrowserCodeStream(appName: string, opts?: PrebootOptions): any {
  opts = normalize(opts);

  let bOpts = {
    entries: [__dirname + '/../browser/preboot_browser.js'],
    standalone: 'preboot',
    basedir: __dirname + '/../browser',
    browserField: false
  };
  let b = browserify(bOpts);

  // ignore any strategies that are not being used
  ignoreUnusedStrategies(b, bOpts, opts.listen, listenStrategies, './listen/listen_by_');
  ignoreUnusedStrategies(b, bOpts, opts.replay, replayStrategies, './replay/replay_after_');

  if (opts.freeze) {
    ignoreUnusedStrategies(b, bOpts, [opts.freeze], freezeStrategies, './freeze/freeze_with_');
  }

  // ignore other code not being used
  if (!opts.buffer) { b.ignore('./buffer_manager.js', bOpts); }
  if (!opts.debug) { b.ignore('./log.js', bOpts); }

  // use gulp to get the stream with the custom preboot browser code
  let outputStream = b.bundle()
    .pipe(source('src/browser/preboot_browser.js'))
    .pipe(buffer())
    .pipe(insert.append('\n\n;preboot.init("' + appName + '",' + stringifyWithFunctions(opts) + ');\n\n'))
    .pipe(insert.append('\n\n;preboot.init("' + appName + '2",' + stringifyWithFunctions(opts) + ');\n\n'))
    .pipe(rename('preboot.js'));

  // uglify if the option is passed in
  return opts.uglify ? outputStream.pipe(uglify()) : outputStream;
}

 let bundleApp = () => {
   return browserify(join(TMP_DIR, 'main'))
     .bundle()
     .pipe(vinylSourceStream(JS_PROD_APP_BUNDLE))
     .pipe(vinylBuffer())
     // Strip comments and sourcemaps
     .pipe(plugins.uglify({
       mangle: true,
       compress: true,
       preserveComments: 'license'
     }))
     .pipe(gulp.dest(JS_DEST));
 };